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Formation of vesicles with an organometallic amphiphile bilayer by

supramolecular arrangement of metal carbonyl metallosurfactants

Elisabet Parera,a Francesc Comelles,

b Ramon Barnadas

‡c and Joan Suades*

a

Received (in XXX, XXX) Xth XXXXXXXXX 200X, Accepted Xth XXXXXXXXX 200X

First published on the web Xth XXXXXXXXX 200X 5

DOI: 10.1039/b000000x

Metallo-vesicles are formed in water medium as a result of the

supramolecular arrangement of molybdenum carbonyl

metallosurfactants. These new kind of surfactants contain a

hydrophobic metal carbonyl fragment and are easily prepared 10

from surfactant phosphine ligands.

The study of molecular self-assembly is a central topic in

supramolecular chemistry because it is a key knowledge in

interdisciplinary areas involving chemistry, biology and new

materials. In this context, metallosurfactants (surfactants that 15

contain a metal atom in the molecular structure) are very

useful compounds since singular arrangements of metallic

compounds can be achieved by means of their molecular self-

assembly.1 Thus, although this is a relatively recent research

field, a wide range of potential applications have been 20

reported, for instance in catalysis,2 magnetic resonance

imaging,3 antiparasitic medications,4 mesoporous materials,5

metallomesogens,6 optoelectronic devices7 and nanoparticles.8

However, in most of the previous studies the amphiphilic

properties of the metallosurfactant are due to the fact that the 25

metal atom acts as the polar head-group of these particular

surfactants. In contrast to this strategy, we have prepared

metallosurfactants by means of surfactant phosphines, thereby

allowing the metal atom to be in any part of the molecule,

since the polar head-group is a sulfonate linked to the 30

phosphine ligand.9, 10 In particular, we present here the

preparation of a new set of metallosurfactants in which the

metal atom is located in a characteristic hydrophobic

environment, being a neutral metal carbonyl. To our

knowledge, there are no studies about the aggregation 35

properties with similar compounds. Only one work has been

reported with metal carbonyls but in that study the alkoxy

Re(I) compound does not have an additional polar head-

group, so it is structurally analogous to the main group of

metallosurfactants in which the transition metal atom 40

coincides with the polar group.11

a Departament de Química, Universitat Autònoma de Barcelona, Edifici

C, 08193 Bellaterra, Spain. Fax: +34935813101; Tel: +34935812893; E-

mail: [email protected] b Institut de Química Avançada de Catalunya, CSIC, Jordi Girona, 18-26

08034 Barcelona, Spain c Departament de Fisicoquímica, Facultat de Farmàcia, Universitat de

Barcelona, Avda. Joan XXIII s/n, 08028 Barcelona, Spain

†Electronic Supplementary Information (ESI) available: [Experimental

details, HRMS spectra and figures with surface tension measurements].

See DOI: 10.1039/b000000x/ ‡Current address: Departament de Bioquímica i de Biologia Molecular,

Edifici M, 08193 Bellaterra, Spain

Two families of new organometallic metallosurfactants were

synthesised by means of the coordination of the surfactant

phosphines Ph2P(CH2)nSO3Na (1, 2, 3) to the fragments

{Mo(CO)5} and {Mo(CO4} as can be seen in the Schemes 1 45

and 2. Hence, complexes 4-6 can be regarded as classical

surfactants with a bulky hydrophobic group, the {Ph2P-

Mo(CO)5} fragment, at the end of the hydrocarbon chain.

50

Scheme 1 Surfactant phosphine ligands 1-3.

Alternatively, complexes 7-9 can be considered bolaform

surfactants since they contain two unities of conventional

surfactants (Ph2P(CH2)nSO3Na ligands) linked by a rigid non

polar group (the {Mo(CO)4} fragment) at the end of the 55

hydrocarbon chains.

Scheme 2 Preparation of molybdenum metallosurfactants (L = 1, 2, 3; pip

= piperidine)

Complexes 4-6 were prepared by direct reaction between 60

[Mo(CO)6] and the respective phosphine using the procedure

reported for TPPTS (triphenylphosphine trisulfonate)12 with

some modifications such as the reaction media and the work-

up of reaction products (Scheme 2). Complexes 7-9 were

prepared by the substitution reaction of piperidine in the cis-65

Page 5 of 21 ChemComm - For Review Only

2004568

Cuadro de texto

Post-print of: Parera Piella, Elisabet et al. “Formation of vesicles with an organometallic amphiphilic bilayer by supramolecular arrangement of metal carbonyl metallosurfactants” in Chemical communications (Royal Society of Chemistry), vol. 47 issue 15 (Mar 2011) p. 4460-4462. The final versión is available at 10.1039/C0CC05493C

2 | Journal Name, [year], [vol], 00–00 This journal is © The Royal Society of Chemistry [year]

[Mo(CO)4(pip)2] complex (pip = piperidine) by the

corresponding phosphine ligand using a procedure also similar

to that reported for TPPTS (Scheme 2).13, 14

All compounds were characterised by the usual spectroscopic

methods and their stability in water medium was studied by 5

31P NMR spectroscopy. Results showed that water solutions

of complexes 4-9 are sufficiently stable to undergo studies of

their aggregation properties (decomposition values were under

5 % in 24 hours).

The metallosurfactant character of 4-9 was proven by surface 10

tension measurements that evidenced in all cases the

characteristic decrease as concentration increases until

reaching the critical micelle concentration (cmc) as shown in

Figure 1.

15

Figure 1 Surface tension measurements for complex 5.

The cmc values for complexes 4-9 are significantly lower than

those for the respective ligand as can be seen in Table 1. A

similar behaviour has been reported for other

metallosurfactants with ML2 stoichiometry. This has been 20

related to the structural analogy between these molecules and

gemini surfactants9 or bolamphiphiles.10 It should be

emphasised that the present study allows a new kind of

comparison because compounds 4-6 and 7-9 are the first

example of two families of similar metallosurfactants with the 25

stoichiometries ML and ML2 that can be compared with the

free surfactant ligands 1-3. It is noteworthy that no significant

differences were observed between the cmc values of ML (4-

6) and ML2 (7-9) complexes. The cmc diminution in 4-6

respect to the free phosphines 1-3 can be associated to an 30

increase in the hydrophobicity as a result of the addition of

the lipophilic carbonyl fragments {Mo(CO)5}. This result is

consistent with the idea that, in contrast to metallosurfactants

in which the transition metal is the polar headgroup, in these

compounds the addition of metal increases the hydrophobic 35

character of the molecule.

The calculus of the area occupied per molecule adsorbed in

the water/air interface from the slope of the linear decrease of

surface tension below the cmc via the Gibbs equation (Γ = -

(dγ/dlog C)/2.303nRT; Γ = surface excess concentration, n = 40

number of molecular species in solution) is a common

approach in the study of surfactants that has recently been

questioned.15 However, we have included these data in Table

1 because they are useful for comparison purposes only. Thus,

the effect of hydrocarbon chain length on this value shows 45

different trends for the three families of compounds displayed

in Table 1. Whereas for the free phosphines (1-3) the data are

nearly identical, a substantial increase is observed from 4 to 6.

This result agrees with the hypothesis that the influence of

chain length in packing at the air-water interface is minimal 50

with ligands 1-3 but it becomes relevant after the addition of

the hydrophobic {Mo(CO)5} fragment. For complexes 7-9, a

relatively small increase is observed from 7 to 8, whereas a

great increment is produced from 8 to 9. This singular

behaviour is consistent with previous data with cis-[PtCl2L2] 55

(L = 1, 2, 3) complexes10 and it concords with the idea that

complex 9 could adopt a double loop conformation in the

interface as is shown in Figure 2.

Table 1 Calculated parameters from surface tension measurements:

critical micelle concentration (cmc), surface excess concentration (Γ), 60

estimated area occupied per molecule adsorbed in the water/air interface

via Gibbs equation (A).

Compound cmc (mM) Γ (mol/cm2) A (Å2)

1 14 (1.7±0.1)×10-10 99

2 4.0 (1.64±0.03)×10-10 101

3 0.5-1.2 (1.6±0.2)×10-10 100

4 2.0 (1.75±0.04)×10-10 95

5 1.2 (9.9±0.3)×10-11 167

6 0.15 (8.9±0.8)×10-11 190

7 1.9 (1.2±0.1)×10-10 140

8 0.84 (8.7±0.3)×10-11 192

9 0.28 (4.9±0.4)×10-11 340

65

Figure 2 Schematic representations of complexes 7-9 in the interface

showing the double-loop conformation for 9 (sulfonate groups are

represented by yellow balls).

The study of supramolecular aggregates formed in water

solutions of compounds 4-9 at concentrations above the cmc 70

was performed by means of Dynamic Light Scattering

spectroscopy (DLS) and cryo-TEM microscopy. The DLS

results agree with the formation of medium and large size

polydisperse vesicles in all cases {average hydrodynamic

diameter of aggregates in nm: 225±4 (4), 147±2 (5), 200±20 75

(6), 250±80 (7), 1300±90 (8), 127±1 (9)}. These findings are

consistent with previous studies that have shown a tendency

for amphiphilic metal complexes to aggregate yielding

vesicles instead of micelles.10, 16, 17 This behaviour has been

related to the changes in the shape of molecules after metal 80

coordination which favours self-assembly as vesicles.10, 17

Cryo-TEM microscopy analysis of water solutions of

compounds 4-9 corroborated the formation of polydisperse

spherical vesicles in all cases. The micrographies show a wide

range of aggregates with some morphological differences as it 85

is nicely shown in Figure 3. This picture is very interesting

because in a sole image we can observe: (a) small unilamellar

vesicles (SUV, small spheres of diameters lower than 100

nm), (b) large unilamellar vesicles (LUV, large spheres of

diameters higher than 100 nm), (c) multilamellar vesicles 90

(MLV, they have an onion-like structure), (d) multilamellar

multivesicular vesicles (they do not have the onion structure,

they consist of many smaller non concentric spheres inside a

Concentration (mM)

0,01 0,1 1 10

Su

rfac

e te

nsi

on (

mN

/m)

30

40

50

60

70

Page 6 of 21ChemComm - For Review Only

This journal is © The Royal Society of Chemistry [year] Journal Name, [year], [vol], 00–00 | 3

larger vesicle).

Figure 3 Cryo-TEM micrograph of a solution of 5 in water

(concentration: 7.3 mM). 5

In summary, we have shown that metallosurfactants with a

metal carbonyl fragment in the hydrophobic part of the

molecule exhibit a tendency to form vesicles in a similar way

as other special surfactants such as fullerene derivatives.18

The main difference is that in the present work the walls of 10

these vesicles contain a metallic amphiphile bilayer as can be

visualized in Figure 4.

This work was supported by the Dirección General de

Investigación (Project CTQ2007-63913). We thank Dr. Emma

Rossinyol for valuable assistance with the cryo-TEM studies, 15

to Prof. Joan Estelrich for DLS measurements and to Ms.

Estel López for the design of Figure 4.

20

Figure 4 Schematic representations of a metallo-vesicle showing the

organometallic amphiphile bilayer (yellow and purple balls respectively

represents sulfonate and {Ph2PMo(CO)5} groups).

Notes and references 25

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6 (a) B. Donnio, Curr. Opin. Colloid Interface Sci., 2002, 7, 371. (b)

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7 (a) N. Terasaki, T. Akiyama, S. Yamada, Langmuir, 2002, 18, 8666.

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Comte, C. Barolo, G. Viscardi, K. Schenk, M. Graetzel, Coord.

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N. Bordenyuk, L. Wu, S. R. P. da Rocha, C. N. Verani, A. V. 60

Benderskii, Langmuir, 2009, 25, 6880. (d) H. J. Bolink, E. Baranoff,

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Repetto, Md. K. Nazeeruddin, Langmuir, 2010, 26, 11461.

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11 P. Thanasekaran, J.Y. Wu, B. Manimaran, T. Rajendran, I. J. Chang,

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12 C. Larpent, H. Patin, Appl. Organomet. Chem., 1987, 1, 529.

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14 D. J. Darensbourg, C. J. Bischoff, Inorg. Chem., 1993, 32, 47.

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1944.

200 nm


1

Formation of vesicles with an organometallic amphiphile bilayer by

supramolecular arrangment of metal carbonyl metallosurfactants

Elisabet Parera,a Francesc Comelles,

b Ramon Barnadas

c and Joan Suades*

a

aDepartament de Química, Universitat Autònoma de Barcelona, Edifici C, 08193 Bellaterra, Spain.

bInstitut de Química Avançada de Catalunya, CSIC, Jordi Girona, 18-26, 08034 Barcelona, Spain

cDepartament de Fisicoquímica, Facultat de Farmàcia, Universitat de Barcelona, Avda. Joan XXIII s/n,

08028 Barcelona, Spain

Table of Contents:

1. General Information 1

2. Synthesis of Complexes 4-9 2

3. High Resolution Mass Spectrometry 5

4. Surface Tension Measurements 11

1. General Information

All reactions were performed under nitrogen using standard Schlenk tube techniques.

Tetrahydrofuran and methanol were distilled (respectively, over sodium/benzophenone and

magnesium) and stored over 3Å molecular sieve. Pentane was dried with 3Å molecular sieve.

Infrared spectra were recorded with a Perkin-Elmer 2000 FT spectrometer. The NMR spectra

were recorded in the Servei de Ressonància Magnètica Nuclear de la Universitat Autònoma de

Barcelona on Bruker DPX-250, DPX-360 and AV400 instruments. Microanalyses were

performed by the Servei d’Anàlisi Química del Departament de Química de la Universitat

Autònoma de Barcelona. Mass spectra and exact mass measurements were respectively obtained

on an Esquire 3000 with electrospray ionization and an ion trap Bruker Daltonics and on a

Bruker microTOFQ with electrospray ionization Apollo of Bruker by Servei d’Anàlisi Química

del Departament de Química de la Universitat Autònoma de Barcelona.

The Dynamic Light Scattering measurements were performed in the Departament de

Fisicoquímica de la Facultat de Farmàcia de la Universitat de Barcelona using a Malvern

Zetasizer ZS90 (Malvern Instruments Ltd, Malvern, UK) equipped with an He-Ne laser. In this


2

device scattered light is detected at 90º and its intensity on the detector is automatically adjusted

in order to achieve an optimal range. This fact allows the analysis of several orders of sample

concentration, avoiding their dilution and, consequently, changes in the phase equilibrium. The

DLS instrument used for these experiments can be used to characterize particles with diameters

in the range 2 nm – 6 µm. All compounds were previously recrystallized. The water solutions of

amphiphiles (4: 10.9 mM; 5: 7.3 mM; 6: 3.4 mM; 7: 10.5 mM; 8: 9.1 mM; 9: 3.7 mM) were

prepared with degassed Milli-Q water. The solutions were previously centrifuged for 2 – 3

minutes at 13000 rpm and then aged for at least 1 hour before measurements. For all DLS

measurements the temperature was 25 ± 0.5 ºC. Each data acquisition was a mean of 10

consecutive analyses and each experiment was repeated three times. The data were analyzed by

cumulant method using the software provided by the manufacturer. Polydispersity index of the

samples corresponded to polydisperse vesicles (4: 0.41±0.05; 5: 0.46±0.02; 6: 0.7±0.2; 7:

0.56±0.06; 8: 0.34±0.05; 9: 0.50±0.01) in agreement with cryo-TEM microscopy analysis.

The microscopy studies were performed in the Servei de Microscòpia Electrònica de la

Universitat Autònoma de Barcelona. Micrographs were obtained using a Jeol JEM-1400 electron

microscope operating at 120 kV and equipped with a CCD multiscan camera (Gatan). The

microscope was equipped with a Gatan cryoholder and the samples were maintained at -177ºC

during imaging. Micro drops (2 µL) of the water solutions of amphiphiles were blotted onto

holey carbon grids (Quantifoil) previously glow discharged in an BAL-TEC MSC 010 glow

discharger unit, which were immediately plugged into liquid ethane at -180 ºC using a Leica EM

CPC cryoworkstation.

2. Synthesis of Complexes 4-9

Complexes 4, 5, 6: The phosphine Ph2P(CH2)nSO3Na {0.22 mmol (0.070 g for 4, 0.082 g for 5

and 0.095 g for 6)} was dissolved in dry methanol (10 mL for 4 and 5; 15 mL for 6) and this

solution was added at room temperature to a solution of [Mo(CO)6] (0.584 g, 2.21 mmol) in

freshly distilled THF (40 mL). The resulting solution was protected from light and heated with a

bath at 80 ºC for 15 hours under nitrogen atmosphere. The obtained yellow solution was cooled,

getting dark as temperature decreases and becoming black at to room temperature. Next, solvent

was evaporated under reduced pressure to dryness to yield a black solid that was washed (3 × 20

mL) with dry pentane in order to remove [Mo(CO)6] excess. Dry methanol (50 mL for 4 and 5;

75 mL for 6) was added to the residual solid and after vigorous stirring the resulting mixture was


3

centrifuged (5000 rpm) and filtered with Celite. The complexes were isolated as brown solids

after evaporation of filtrate to dryness under reduced pressure.

[Mo(CO)5(1)](4): The above procedure leads to 85 mg of 4 (70 %). IR (CH2Cl2, cm-1

): 2073,

1990, 1945 {ν(CO)}. 31

P{1H}-NMR (CD3OD, δ in ppm): 26.7 (s).

1H-NMR (CD3OD, δ in ppm):

2.62 – 2.73 (m, PCH2), 2.89 – 3.00 (m, CH2S), 7.45 – 7.69 (m, Ph). MS-ESI (negative mode,

m/z): 446.8 ([M-3CO-Na]-, 100 %), 474.8 ([M-2CO-Na]

-, 15 %). HRMS (ESI) calcd for

C19H14MoO8PS ([M-Na]-) 530.9209, found 530.9199. Anal. Found: C, 41.12; H, 2.60; S, 5.63.

Calcd for C19H14MoNaO8PS: C, 41.32; H, 2.56; S, 5.81.


): 2072,

1988, 1944 {ν(CO)}. 31



1.32 – 1.49 (m, PCH2CH2CH2CH2), 1.56 – 1.70 (m, CH2CH2S), 2.41 – 2.56 (m, PCH2), 2.70 –

2.80 (m, CH2S), 7.42 – 7.68 (m, Ph). MS-ESI (negative mode, m/z): 586.9 ([M-Na]-, 100 %),

HRMS (ESI) calcd for C23H22MoO8PS ([M-Na]-) 586.9836, found 586.9820. Anal. Found: C,

45.28; H, 3.53; S, 5.12. Calcd for C23H22MoNaO8PS: C, 45.41; H, 3.64; S, 5.27.


): 2071,

1988, 1943 {ν(CO)}. 31



1.13 – 1.47 (m, PCH2(CH2)7), 1.71 – 1.82 (m, CH2CH2S), 2.41 – 2.50 (m, PCH2), 2.73 – 2.82 (m,

CH2S), 7.44 – 7.59 (m, Ph). MS-ESI (negative mode, m/z): 642.9 ([M-Na]-, 100 %). HRMS

(ESI) calcd for C27H30MoO8PS ([M-Na]-) 643.0464, found 643.0447. Anal. Found: C, 48.45; H,

4.37; S, 4.56. Calcd for C27H30MoNaO8PS: C, 48.40; H, 4.55; S, 4.83.

Complexes 7, 8, 9: The phosphine Ph2P(CH2)nSO3Na {0.119 g (0.37 mmol) for 7, 0.208 g (0.56

mmol) for 8, 0.219 g (0.51 mmol) for 9} was dissolved in dry methanol (10 mL for 7 and 8; 20

mL for 9) and this solution was slowly added at room temperature to a solution of cis-

[Mo(CO)4(pip)2] (pip = piperidine, 0.070 g, 0.19 mmol) in dry THF (10 mL). The resulting

solution was protected from light and allowed to stir at room temperature for 3 hours under

nitrogen atmosphere. At this point, a clear yellow solution should be obtained. If some turbidity

was observed, it can be related with the use of solvents that were not dry enough. This clear

yellow solution was evaporated under reduced pressure to dryness to yield a yellow solid. Dry

methanol (0.5 mL for 7 and 8; 1.5 mL for 9) was added to this solid and after vigorous stirring

the resulting mixture was centrifuged (13000 rpm). Freshly distilled diethyl ether was dropwise

added to the filtrate until the precipitation of a yellow solid is complete (≈ 2 mL). The precipitate

was isolated by centrifugation (13000 rpm), washed with diethyl ether (2 × 1 mL) and dried

under reduced pressure. Complexes 7, 8, 9 were isolated as yellow solids.


4

cis-[Mo(CO)4(1)2](7): The above procedure leads to 127 mg of 7 (82 %). IR (CH2Cl2, cm-1

):

2020, 1925, 1897 {ν(CO)}. 31


1H-NMR (CD3OD, δ in

ppm): 2.43 – 2.62 (m, PCH2), 2.69 – 2.84 (m, CH2S), 7.24 – 7.90 (m, Ph). 13

C-NMR (CD3OD, δ

in ppm): 28.3 (AXX’, 3 lines, 1JC-P+

3JC-P’ = 20.4 Hz, PCH2), 46.4 (s, CH2S), 128.2-135.7

(multiple signals, Ph), 209.3 (t, 2JC-P = 9.4 Hz, CO cis to the two P atoms), 214.8 (AXX’, 3 lines,

2JC-P+

2JC-P’ = 15.8 Hz, CO trans and cis to P atoms). MS-ESI (negative mode, m/z): 818.8 ([M-

Na]-, 55 %). HRMS (ESI) calcd for C32H28MoNaO10P2S2 ([M-Na]

-) 818.9550, found 818.9550.

Anal. Found: C, 45.34; H, 3.56; S, 7.31. Calcd for C32H28MoNa2O10P2S2·0.5CH4O: C, 45.57; H,

3.53; S, 7.49.

cis-[Mo(CO)4(2)](8): The above procedure leads to 150 mg of 8 (85 %). IR (CH2Cl2, cm-1

):

2015, 1914, 1896, 1868 {ν(CO)}. 31


1H-NMR

(CD3OD, δ in ppm): 1.07 – 1.16 (m, PCH2CH2), 1.16 – 1.25 (m, PCH2CH2CH2CH2), 1.59 – 1.69

(m, CH2CH2S), 2.00 – 2.08 (m, PCH2), 2.66 – 2.73 (m, CH2S), 7.31 – 7.41 (m, Ph). 13

C-NMR

(CD3OD, δ in ppm): 23.9 (s, PCH2CH2), 24.4 (s, CH2CH2S), 28.0 (s, CH2CH2CH2S), 30.3

(AXX’, 3 lines, 2JC-P+

4JC-P’ = 12.8 Hz, PCH2CH2CH2), 32.2 (AXX’, 3 lines,

1JC-P+

3JC-P’ = 21.7

Hz, PCH2), 51.0 (s, CH2S), 127.9-137.1 (multiple signals, Ph), 210.0 (t, 2JC-P = 9.4 Hz, CO cis to

the two P atoms), 215.3 (AXX’, 3 lines, 2JC-P+

2JC-P’ = 15.9 Hz, CO trans and cis to P atoms).

MS-ESI (negative mode, m/z): 931.0 ([M-Na]-, 70 %). HRMS (ESI) calcd for

C40H44MoNaO10P2S2 ([M-Na]-) 931.0805, found 931.0795. Anal. Found: C, 49.78; H, 5.02; S,

6.28. Calcd for C40H44MoNa2O10P2S2·CH4O: C, 50.00; H, 4.91; S, 6.51.


): 2018,

1917, 1900, 1875 {ν(CO)}. 31


1H-NMR (CD3OD, δ in

ppm): 1.01 – 1.31 (m, PCH2(CH2)6), 1.31 – 1.47 (m, CH2CH2CH2S), 1.70 – 1.82 (m, CH2CH2S),

1.97 – 2.08 (m, PCH2), 2.73 – 2.81 (m, CH2S), 7.27 – 7.49 (m, Ph). 13

C-NMR (CD3OD, δ in

ppm): 23.7 (s, PCH2CH2), 24.5 (s, CH2CH2S), 28.3 (s, CH2CH2CH2S), 28.6-28.9 {four singlets,

PCH2CH2CH2(CH2)4}, 30.3 (AXX’, 3 lines, 2JC-P+

4JC-P’ = 12.5 Hz, PCH2CH2CH2), 32.2 (AXX’,

3 lines, 1JC-P+

3JC-P’ = 21.6 Hz, PCH2), 51.3 (s, CH2S), 127.9-137.3 (multiple signals, Ph), 210.0

(t, 2JC-P = 9.7 Hz, CO cis to the two P atoms), 215.3 (AXX’, 3 lines,

2JC-P+

2JC-P’ = 16.0 Hz, CO

trans and cis to P atoms). MS-ESI (negative mode, m/z): 1043.1 ([M-Na]-, 63 %, 510.0 ([M-

2Na]2-

, 100 %). HRMS (ESI) calcd for C48H60MoNaO10P2S2 ([M-Na]-) 1043.2032, found

1043.2032. Anal. Found: C, 53.73; H, 5.77; S, 5.69. Calcd for C48H60MoNa2O10P2S2·0.5 CH4O:

C, 53.89; H, 5.78; S, 5.93.


5

3. High Resolution Mass Spectrometry

a) Calculated and experimental isotopic distribution for [Mo(CO)5(1)](4)

[M – Na]- : C19H14MoO8PS

Calculated: 524.9221, 525.9253, 526.9206, 527.9214, 528.9207, 529.9218, 530.9209,

531.9235, 532.9224, 533.9255, 534.9231.

Experimental: 524.9214, 525.9236, 526.9199, 527.9205, 528.9198, 529.9211, 530.9199,

531.9231, 532.9215, 533.9246, 534.9240.

m/z

m/z

Calculated isotopic distribution

[M – Na]-

Experimental isotopic distribution

[M – Na]-


6

b) Calculated and experimental isotopic distribution for [Mo(CO)5(2)](5)


Calculated: 580.9847, 581.9879, 582.9833, 583.9841, 584.9834, 585.9845, 586.9836,

587.9863, 588.9852, 589.9882, 590.9864.

Experimental: 580.9830, 581.9857, 582.9805, 583.9823, 584.9816, 585.9826, 586.9820,

587.9831, 588.9821, 589.9836, 590.9734.


[M – Na]-


[M – Na]-


7

c) Calculated and experimental isotopic distribution for [Mo(CO)5(3)](6)


Calculated: 637.0473, 638.0506, 639.0460, 640.0467, 641.0462, 642.0473, 643.0464,

644.0490, 645.0479, 646.0509, 647.0497.

Experimental: 637.0460, 638.0484, 639.0445, 640.0449, 641.0445, 642.0451, 643.0447,

644.0473, 645.0464, 646.0492, 647.0489.


[M – Na]-


[M – Na]-


8

d) Calculated and experimental isotopic distribution for cis-[Mo(CO)4(1)2](7)

[M – Na]- : C32H28MoNaO10P2S2

Calculated: 812.9559, 813.9592, 814.9548, 815.9555, 816.9550, 817.9559, 818.9550,

819.9573, 820.9562, 821.9590, 822.9572.

Experimental: 812.9556, 813.9593, 814.9543, 815.9554, 816.9549, 817.9561, 818.9550,

819.9576, 820.9559, 821.9591, 822.9580.


[M – Na]-


[M – Na]-


9

e) Calculated and experimental isotopic distribution for cis-[Mo(CO)4(2)2](8)


Calculated: 925.0811, 926.0844, 927.0803, 928.0808, 929.0805, 930.0814, 931.0805,

932.0828, 933.0818, 934.0843, 935.0834.

Experimental: 925.0785, 926.0813, 927.0779, 928.0788, 929.0781, 930.0792, 931.0795,

932.0816, 933.0803, 934.0824, 935.0815.

m/z

m/z


[M – Na]-


[M – Na]-


10

f) Calculated and experimental isotopic distribution for cis-[Mo(CO)4(3)2](9)


Calculated: 1037.2063, 1038.2096, 1039.2059, 1040.2062, 1041.2059, 1042.2068,

1043.2059, 1044.2082, 1045.2073, 1046.2097, 1047.2095, 1048.2103.

Experimental: 1037.2021, 1038.2072, 1039.2021, 1040.2029, 1041.2029, 1042.2029,

1043.2032, 1044.2042, 1045.2028, 1046.2067, 1047.2075, 1048.2011.

Experimental isotòpic distribution

[M – Na]-


[M – Na]-


11

4. Surface Tension Measurements. The surface tension measurements of the aqueous solutions

were performed in the Departament de Tecnologia de Tensioactius de l’Institut de Química

Avançada de Catalunya (IQAC-CSIC) at 25 °C with a Krüss K-12 automatic tensiometer

(Hamburg, Germany) equipped with a Wilhelmy plate. All compounds were previously

recrystallized and lyophilized. The water solutions of amphiphiles were prepared with degassed

Milli-Q water. The different solutions were prepared by dilution of a concentrated sample and

then aged for at least 30 min before the determinations. The stability criterion for surface tension

values was tuned to ± 0.1 mN/m for five consecutive measurements. The cmc values were taken

from the intersection of two linear sections obtained in the graphical plots of surface tension

versus logarithm of the concentration. The area occupied per molecule adsorbed at the water/air

interface, expressed in Å2, was obtained from the equation A = 10

16/NAΓ, where NA is

Avogadro’s number and Γ the surface excess concentration in mol/cm2, calculated according to

the Gibbs equation: Γ = -(d γ/d log C)/2.303nRT, where n is the number of molecular species in

solution (n = 2 for compounds 4-6 and n = 3 for compounds 7-9), and (d γ/d log C) is the slope

of the linear part of the graph obtained immediately below the cmc.


12

a) Surface tension measurements for complexes (4-6)

0,0001 0,001 0,01 0,1 1 10

20

30

40

50

60

70

80

0,0001 0,001 0,01 0,1 1 10

Su

rfac

e te

nsi

on

(m

N/m

)

20

30

40

50

60

70

80

Concentration (mM)

0,0001 0,001 0,01 0,1 1 10

20

30

40

50

60

70

80

(5)

(6)

(4)


13

b) Surface tension measurements for complexes (7-9)

0,001 0,01 0,1 1 10

20

30

40

50

60

70

80

0,001 0,01 0,1 1 10

Su

rfac

e te

nsi

on

(m

N/m

)

20

30

40

50

60

70

80

Concentration (mM)

0,001 0,01 0,1 1 10

20

30

40

50

60

70

80

(8)

(9)

(7)


TABLE OF CONTENTS ENTRY

SUMMARY: Self-assembly of new metal carbonyl metallosurfactants prepared from

surfactant phosphines leads to the formation of metallo-vesicles with an organometallic

amphiphile bilayer.

GRAPHIC:

Surfactant phosphine

Metallo-vesicle

Mo(CO)6

Ph2P(CH2)nSO3Na


Documents

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